Interaction between histamine and morphine at the level of the hippocampus in the formalin-induced orofacial pain in rats.
Journal Title: Pharmacological Reports - Year 2011, Vol 63, Issue 2
Abstract
The present study explored the interaction between histaminergic and opioidergic systems at the level of the hippocampus in modulation of orofacial pain by intra-hippocampal microinjections of histamine, pyrilamine (an antagonist of histamine H(1) receptors), ranitidine (an antagonist of histamine H(2) receptors), morphine (an opioid receptor agonist) and naloxone (an opioid receptor antagonist) in separate and combined treatments. Orofacial pain was induced by subcutaneous (sc) injection of formalin (50 μl, 1%) in the upper lip region and the time spent face rubbing was recorded in 3 min blocks for 45 min. Formalin (sc) produced a marked biphasic (first phase: 0-3 min, second phase: 15-33 min) pain response. Histamine and morphine suppressed both phases of pain. Histamine increased morphine-induced antinociception. Pyrilamine and ranitidine had no effects when used alone, whereas pretreatments with pyrilamine and ranitidine prevented histamine- and morphine-induced antinociceptive effects. Naloxone alone non-significantly increased pain intensity and inhibited the antinociceptive effects of morphine and histamine. The results of the present study indicate that at the level of the hippocampus, histamine through its H(1) and H(2) receptors, mediates orofacial region pain. Moreover, morphine via a naloxone-reversible mechanism produces analgesia. In addition, both histamine H(1) and H(2) receptors, as well as opioid receptors may be involved in the interaction between histamine and morphine in producing analgesia.
Authors and Affiliations
Esmaeal Tamaddonfard, Amir Erfanparast, Amir Abbas Farshid, Emad Khalilzadeh
Keywords
Related Articles
- EP ID EP108224
- DOI -
- Views 100
- Downloads 0
Effects of different priming doses of fentanyl on fentanyl-induced cough: a double-blind, randomized, controlled study.
Background: Fentanyl-induced cough is not an uncommon phenomenon during the induction of general anesthesia. A preliminary randomized controlled study was designed to observe the effects of different priming doses of fen...
Effects of catecholamines on blood pressure in the long bone marrow cavity in rats with bisphosphonate-induced osteopetrosis.
Osteopetrosis is a congenital metabolic bone disease characterized by skeletal sclerosis resulting from defective osteoclast-mediated bone resorption. The disease may, inter alia, be caused by the administration of bisph...
Cucurmosin induces the apoptosis of human pancreatic cancer CFPAC-1 cells by inactivating the PDGFR-β signalling pathway.
Background: Pancreatic cancer treatment is limited and effective drugs are needed. We investigated cucurmosin (CUS)-induced apoptosis in cystic fibrosis pancreatic adenocarcinoma cells (CFPAC-1) and a possible mechanism...
Radiofrequency denervation with or without addition of pentoxifylline or methylprednisolone for chronic lumbar zygapophysial joint pain.
Radiofrequency neurolysis of lumbar medial branch is currently the only proven way to treat patients with chronic lumbar zygapophysial joint pain, however, in some patients it can cause transient postoperative pain due t...
Influence of ethacrynic acid on the anticonvulsant activity of conventional antiepileptic drugs in the mouse maximal electroshock seizure model.
The aim of this study was to determine whether ethacrynic acid (EA), a loop diuretic with anticonvulsant activity, would affect the protective action of the conventional antiepileptics (AEDs) carbamazepine (CBZ), phenyto...